Q: I was out at my pond today and it is still partially covered with ice. I have a de-icer and aeration – isn’t that enough to keep the ice off my pond?

Mark – Buffalo, NY

A: During these frigid months of the year, a hole in the ice means the difference between life and death for your pond fish. That opening allows oxygen to flow into the liquid water while it dissipates harmful gases caused by decaying debris and fish waste into the air.

Bubblers and de-icers both keep a hole open in the ice, but they go about it differently.

Bubblers, like the ones found in Airmax® PondAir™ Aeration Kits, are designed to gently and quietly move the water surface, and that action keeps a hole open in the ice. The aerator also delivers oxygen to the lower levels in your pond while bringing harmful gases to the surface to be released.

De-icers, such as the Thermo-Pond De-icer, melt surface-forming ice and create a gas exchange vent in the ice. While effective, during cold windy nights they may not be be enough to keep a hole open on their own.

Bubbler-De-icer Combos, like Airmax® PondAir™/Thermo-Pond De-icer Combo, is an energy-efficient option. Because the aerator will bring harmful gases to the surface and your de-icer helps to keep the hole melted, you’ll be sure to keep the ice vent open.

The bubblers, de-icers and combos are not designed to warm the water or keep the entire pond surface ice free. They’re meant to keep an opening for gas exchange, which is all that’s needed for the fish in your pond.

As long as the equipment you have in the pond is sized correctly (see your manual for details on what yours can effectively handle), you won’t need a larger hole. Your fish are less active, not eating and producing less waste, and so they won’t have the gas exchange requirements they do in the warmer months.

If your vent does freeze over during extra cold temperatures, simply pour hot water on the ice where the hole once was. It’ll melt the hole back open – and your fish can breathe a sigh of relief!

A: With winter officially starting in just one week, the cold weather is settling in across the country. Since your fish don’t have miniature submerged Koi calendars to check, what is it that tells your fish it is time to hibernate?

Koi are cold-blooded creatures, which means their body temperatures and activity levels are directly correlated with the ambient temperature. Koi are active and alert when their environment is warm and will start to slow down as the water temperature decreases. Once the water temperatures start to dip below 46°F your fish tend to stop eating and will retreat to the bottom of the pond. Your fish use the decrease in temperature along with the shortening day lengths as a trigger to prepare for winter.

As the water begins to cool, your fish will become less active as their bodily functions slow down. Less activity means a slower digestive process, less demand for food. It is this decrease in food digestion that warrants the use of wheat germ based foods like Pond Logic® Spring & Fall Fish Food. These types of food are easier to digest that regular food reducing the risk of leaving undigested food to rot inside a dormant fish, which can potentially be fatal.

As the temperatures continue to decline towards 40°F, the blood flow and respiratory rate of the fish will drop to an extremely low rate where their body is hardly functioning. You may hear people say that your Koi are sleeping in the winter and while fish do sleep this goes way beyond the standard drop in bodily functions associated with some much needed shut-eye. This extreme internal slow down ensure survival with even the most limited resources with cases of dormant fish lasting 150 days without food.

The whole over-wintering scenario sounds a little extreme to us but it is truly a natural and normal process for your fish. They do not require much attention in the winter but there are a few things you can do to ensure their winter break is a success. When a layer of ice begins to form over the pond, maintain an opening for gas exchange using an aeration kit or pond de-icer, like the PondAir™ & Thermo-Pond Combo.

Pond Talk: What do you do to help your fish through the winter season?

Q: If I run my waterfall pump for a few hours a day during winter, will my fish be OK?

Lenny – Waggoner, IL

A: While it may be beautiful to run your waterfall during winter, it is not always recommended. A waterfall pump moves and circulates oxygenated water through the water column, but if you run it for just a few hours each day, your fish – and your pocketbook – may suffer. Here’s why.

Oxygen Starved: First of all, your fish need plenty of fresh oxygen, even when they’re semi-dormant in the wintertime. A few hours of circulation from a waterfall pump won’t keep a hole in the ice or infuse enough oxygen into the water, so the lack of fresh air will stress out your finned pals and put them at risk for disease.

Ice Dams: If you run your waterfall pump in northern climates during near- or sub-freezing temperatures, ice dams can develop and grow in size, diverting water from the pond. For this reason, you’d need to keep an eye on your water level – particularly if you have a longer stream. When the water level gets too low, your pump could become damaged, which means you’ll need to fork out some cash to replace it.

Overstressed Pump: Speaking of replacing a pump, take a look at your pump’s manual. Does it say that your pump is it designed for use in freezing temperatures? Generally speaking, pumps should be at least 2,000 GPH to operate in the winter.

Big Energy Bill: The cost of running a waterfall pump can easily top $100 a month. The cost of running a de-icer alone to keep a hole in the ice for gas exchange can cost up to $75 a month. Those aren’t cheap options! An aerator; however, is a cost-effective solution that’ll only cost you around $1.70 a month. In addition, you can use aerators throughout the year.

Because of the risk of damaging the waterfall pump and not providing enough oxygen to your fish – along with the high cost of running it all the time – we recommend removing the pump this winter and replacing it with an aerator.

Stowing the Pump

When you remove your pump, submerge it in a 5-gallon bucket of water to keep all its seals lubricated and store it indoors in a place that won’t freeze. Blow out the water and debris in your tubing with an air compressor and cap it off. Drain the skimmer boxes below the weir door. And spray your filter media off with a hose, pump out any water in the filter box and give it a good scrubbing.

Installing Aeration

Once your pump is removed and stored for the season, install an aeration system that’s sized right for your pond. KoiAir™ Aeration Kits, are designed for ponds up to four feet deep and 16,000 gallons, includes a compressor, airline and a diffuser plate. PondAir™ Aeration Kits are suited for ponds up to two feet deep and 2,000 gallons, includes a compressor, airline, check valves and air stones. Simply connect the diffuser plate or air stones to the compressor, submerge the plate/stones and plug it in, and you’re good to go!

You’ll be delivering oxygen to your fish, keeping a hole in the ice and preserving your waterfall pump – and saving a bunch of your hard-earned money.

A: A de-icer is an important piece of equipment in areas where water features freeze over during the winter. This little device maintains a small opening in the ice, which allows harmful gas to escape into the air allowing for efficient air exchange. It can be the difference between life and death for the fish and other inhabitants in your pond.

Which de-icer is best for your situation? It will depend on how many gallons your pond holds, and if you’re using it alone or with an aeration system.

First, here’s what we recommend for de-icers based on the size of your pond:

These de-icers do a great job, but keep in mind that they can be expensive to run non-stop during the cold months. A 1,500 watt de-icer can cost up to $75.00 to operate. That’s a big bill for a small hole!

That’s where an aeration system comes into play.

Aeration systems – can help maintain a hole in the ice while adding oxygen and are infinitely more energy-efficient than pond de-icers. When used in tandem, aeration can significantly reduce the wattage requirements of your pond de-icer, allowing the use of a smaller 100 watt de-icer. It’ll cut energy costs and save you money all season long. For example a 2,000 gallon pond using the PondAir™ 4 and 100 Watt Thermo-Pond De-Icer will cost $5.40 per month instead of $75.00 using a de-icer alone. Not a bad deal!

Q: I have a de-icer but my pond totally froze over. Help! What do I do?

Maggie – Carlisle, PA

A: Sounds like your pond fell victim to the 2014 Polar Vortex! When frigid weather persists for days on end – like those way-below-zero temperatures endured by a large swath of the country earlier this month – a pond can completely freeze over, even if a higher-watt de-icer and aerator are used. The ice-melting combination works great in most scenarios, but it just can’t keep up in extreme conditions.

If your pond has been totally frozen over for a day or so, your fish will be fine. But if it has been more than a few days, your pond pals could be at risk of oxygen deprivation or overexposure to dangerous gases trapped beneath the ice.

So what do you do?

Let’s start with what not to do – and that’s to try to smash the ice with a chisel or blunt object. The sound and vibration of that pounding on the ice amplify underwater, which can stress out your fish. They’re already unhappy, and so you certainly don’t want to make them endure more trauma!

Instead, use a pot of hot water to melt away the ice. If it’s particularly thick, you might need to repeat the process several times to open a complete hole in the frozen stuff. While the temperatures remain frigid, check on the pond every few days to make sure the hole is still open; if it freezes over again, use hot water to open the hole back up.

With another two-plus months of winter ahead of us, it’s not too late to add a de-icer to your pond if you don’t already have one. Simply place a unit, like the K&H Thermo-Pond De-Icer, on the ice and turn it on. It will heat up and melt through the ice – as long as temperatures aren’t too extreme!

Pond Talk: How did your pond fare during these extreme frigid January temperatures?

A: If Jack Frost is blowing in a doozy of a blizzard, you should definitely take the net off your pond. As they accumulate, snow and ice can get heavy enough to collapse the net into your water feature—and that could endanger your dormant fish if they get tangled in the sunken net.

Before the storm passes through, remove your net and store it in your garage or shed, and add a K&H™ Perfect Climate™ De-Icer to your pond. The thermostatically controlled unit, which works above or below the water surface, will melt ice that forms around it, keeping a small hole open for gas exchange.

What About Debris?

If you’re worried about leaves and other organic material landing in your pond, keep your 3-in-1 Pond Tool handy and remove anything that blows in during the storm. The telescoping aluminum handle, which extends 5 feet, will allow you to easily remove that muck-causing debris.

What About Predators?

If you’re concerned that raccoons, blue herons or other predators will battle the snowy elements to grab a sushi dinner from your pond, submerge some Nycon Koi Kastle Fish Shelters in your pond. These molded black plastic or fiberglass mesh shelters, which come in multiple sizes including lengths of 7 ½, 13, 18, 21½ and 24 inches, provide safe refuge for your koi and other fish. Simply position them in the deepest areas of your pond.

Depending on where you live, you can re-install your net again once the snow storm blows by. But if you expect a prolonged period of snow and ice, leave the net off for the season. Good luck, and stay warm and dry!

Pond Talk: What pond toys do you hope Santa brings for you this holiday season?

Q: My pond is 18 inches deep. Can I overwinter my fish in my water garden?

Jessica – Hope Valley, RI

A: Great news! Unless you live in an extremely frigid climate, your pond is at the minimum depth required for overwintering fish in a pond. Though 24 inches or deeper is better, 18 inches should give your finned friends enough room to ride out the cold temperatures—as long as you keep a hole open in the ice.

Freezing winter temperatures will create a solid layer of ice on your pond’s surface. Below the ice sheet, decaying vegetation and organic matter release harmful gases, like ammonia, which can build up and kill your fish. A hole in the ice will allow for gas exchange. The oxygen will enter the pond, the gases will escape, and your fish will stay happy and healthy while they’re hibernating.

To keep that hole open, here’s what you’ll need based on your zone:

Occasional Below-Freezing Temps: For temperature zones that get the occasional below-freezing day or low nighttime temperatures, use an adjustable air stone aerator, like the Airmax® PondAir™ (up to 2,000 gallons) or Airmax® KoiAir™ (up to 16,000 gallons). One of these units will infuse your pond with oxygen while remaining quiet and cost-effective.

Long Stretches of Freezing Temps: For temperature zones that see long stretches of freezing temperatures, we recommend these options, below, based on how many gallons your pond holds. The aerator-deicer combo will give your smaller water garden the one-two punch it needs to vent harmful gases and keep your fish safe, while the more powerful KoiAir will sufficiently aerate larger ponds: